From mboxrd@z Thu Jan 1 00:00:00 1970 From: Goswin von Brederlow Subject: Re: Why does one get mismatches? Date: Thu, 28 Jan 2010 21:24:46 +0100 Message-ID: <874om6m0z5.fsf@frosties.localdomain> References: <201001252043.o0PKhseR027690@wind.enjellic.com> <27F5783C-96DC-4B04-A3EF-D5E7F5F1DD6B@crc.id.au> <87iqamxf4l.fsf@frosties.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: (Tirumala Reddy Marri's message of "Thu, 28 Jan 2010 11:03:59 -0800") Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids "Tirumala Reddy Marri" writes: > I just tried and miss-match count is zero. Interesting, is XOR engine > doing something wrong ? . Then I ran a test where I raw-write the file > to /dev/md0. Then did the raw-read for the same size. In this case XOR > matched as expected. Then I failed a drive using "mdadm -f /dev/md0 > /dev/sda". Then I read the same size data again from /dev/md0. And > checksum matches too. > What is this mean XOR engine is doing right thing. But "chec/repair" > test is not functioning properly with XOR-engine ? > > Or is this something to do with how the buffers are handled ? may they > are cached ? > > > -Marri No idea. But if everything works without the XOR engine and gives mismatches with then I would think there is a software or hardware error there and not in the cable or disks. MfG Goswin